(Auteur) Given the rising availability of alternative ways of spatial data mapping, there is a growing need to study their usability. An important aspect here is the diversity of the cartographic visualizations that are used to draw conclusions about the usability of various mapping techniques. In our study we evaluated the usability of six various mapping techniques used in presenting spatial accessibility, taking into consideration four components: effectiveness and efficiency (objective criteria) and graphical attractiveness and user-perceived effectiveness (subjective criteria). Using Internet questionnaires, we conducted a graphical perception experiment with respondents performing tasks on a hypothetical monocentric road network model displayed using mapping techniques of spatial accessibility, differing in the applied parameters of graphical and non-graphical factors influencing effectiveness and efficiency. The results showed that non-graphical factors had a greater influence than the graphical factors. In total usability comparison the three-dimensional (3D) point technique was ranked the highest, while the worst result was achieved by the 3D area technique. The proposed graphical form of study results made it possible to compare the influence of various effectiveness factors, to analyze mapping techniques in terms of considered criteria and finally to present their total usability using a chart inspired by Uhorczak’s typogram.

(Auteur) Crisis maps and visualizations utilized routinely by international agencies, humanitarian organizations, and non-governmental organizations for aid and relief activities commonly require complex sets of map symbols. However, effective map symbology for humanitarian relief purposes entails several challenges, including consideration of the following: (1) taxonomy development, (2) symbol design issues, (3) promulgation and sharing of map symbols, and (4) standardization of symbols within and among organizations. This paper discusses these key challenges to the design and use of crisis map symbology through a review of the cartographic literature as well as results collected from a survey targeted at humanitarian organizations from around the world. The survey was designed to gather information on current symbology design and use practices in order to understand common challenges. Survey results confirm agreement in the persistence of these four primary symbology challenges, especially the importance of intuitive symbol design. Respondents disagreed most about the adequacy of current crisis map symbology standards as well as the ease in which standards may be implemented within and across organizations. Survey results suggest the need for expert systems designed specifically for symbology design to support humanitarian relief activities.

(auteur) The impetus induced by the development of multi-scale, multi-style maps calls for thinking our resources and protocols with greater interoperability. In the field of toponymy, this requires, in particular, thinking of categories and their structuring with more granularity. Assuming that typography, as a device for visualizing toponyms, is a tool whose potential is still under-exploited, we ask ourselves how the field of typographic design can improve our understanding of toponymic categories and help to structure them in a multi-scale logic. The approach adopted to answer this question is to analyse several existing maps to find good and bad practices. We identified different styles of place names and we built a typology of text features in the surveyed maps. The surveyed maps are the 1 : 35 000 scale, in IGN-France, OSM and GoogleMaps portals.

(Auteur) Rock depiction in Swiss topographic maps has evolved from humble line drawings into expressive renderings indicating slope, aspect and traversability. In this paper, an automatic method to derive monochrome Swiss-style rock hachures from a raster elevation model is presented. The proper placement and light modulation of the linear strokes depend on the availability of sound foundations for both terrain generalization and relief shading, for which two novel methods are introduced. The generalization applies line integral convolution along slope lines to the elevation values. The resulting smoothed raster has the footprint of its steep faces enlarged to increase the map space available for steep faces. The shaded relief is generated with the focus on terrain edges, unlike common raster cell-based methods. The rock hachures are modulated according to the grey values of the shaded relief. Finally, we present two topographic maps that demonstrate this new method of depicting relief.

(Auteur) Glyphs are small geometric shapes that in geovisualization are often used to represent multidimensional spatial data. The aim of this study is to investigate the effectiveness of their two types – star and polyline glyphs, as they can encode the same message and can provide similar functionality. Thus, if the two glyph types are similar and can be used for the same data, the question arises as to which of them better facilitates various user tasks. To address this question, an empirical study of 26 individual users is conducted to investigate differences in user performance for polyline and star glyphs shown either in a grid plot or on a map display. In this study, a task-based approach with eye-tracking is applied, as well as a subjective questionnaire and a psychological test of cognitive style. The finding is that polyline glyphs better facilitate tasks when datapoint values in glyphs are to be read, whereas star glyphs are better when a visual search among glyphs is to be done. Moreover, the results reveal that the map display works better than the grid plot. If star glyphs are to be used, the key (legend) needs to be better incorporated into a visual interface.